Method of spot welding



J. C. SANDER.

METHOD 0F SPDT WELDING. APPLICATION FILED M^Y 1o.192o.

1,416,883. Patented May 23,1922.

j) K// Y Afi? 89 UNITED lSTATES PATENT ori-'ICE `JACoB C. SANDER., OE LYNN, MASSACHUSETTS, ASSICNR To THOMSON SECT WELDEE COMPANY, or BOSTON, MASSACHUSETTS, A CORPORATION or MASSACHUSETTS.

METHOD OE SPOT WELDING.

To all w hom t concern.'

Be it known that I, JACOB SANDER, a

citizen of the United States, and aresident of Lynn, in the county of Essex and Statel of Massachusetts, have invented certain lnew,l

and useful Improvements in Methods of Spot Welding, of which the following is a specification. y

My present invention relates'tofelectric Awelding processes, particularly applied to known process of spot welding.

A further object is to eifect a result which in the finished article will give the external impression that the parts are riveted tof pgether.

The invention consists i-n the-improved method or process of Spotwelding hereinT 'after more particularly described and then Specified in the claims.

In the accompanying drawings, Fi 1 is a rcross-section through work assemb ed bel vtween electrodes to be -used in carrying `out the present invention.A

vridge 5,k the depressin (i F 1g. `2 is a similar welding operation'. n

in line with the'weld.

Fig. 4 is a plan view tion of the work.

of the welded por- In the drawings l land i2 indicates the su,-

perposed plates or other partswhich it is.

derslile'd to secure together by a welded union.

e tween electrodes 3, 4, preferably circular in cross-section, of an electric resistance welding machine of any suitable. character, the details and mode of operation of which arev well known and' understood by those skilled in'theart." f'

' The electrodes .Aandl Contact with the outer surfaces of the work onopposite'sides and are aligned with each other. The ontact face of-each` electrode' is, provided with'l an annularf'ringlo'r ridge 5` surrounding a of' the .'"workf initially.,` bnl on the-.ring for ing out of conn tact with the plates Vin the initial stage of the process. 4 f

vview at the end of the plates are-'assembled together be-.v

Speqication of Letters Patent. Patented yMay 23, 1922 Application mea May 1o,

1920. Serial No. 380,082.

Upoii passing the electric heating current fluid as the electrodes do not contact with it (due to the depressions 6) and therefore do not carry the heat away from that part.

Upon applyin the usual welding pressure the plates arev rstA pressed together in an annular ring caused by the ridge 5. The continuing of this pressure upsets the heated spot sufficiently to cause the material of the heated section to bulge up and Contact with the-bottom .of the depressions 6. When the final welding pressure ois applied the deressions or cavities 6 apply pressure to the ighlyheated center of the spot and cause thls ypart to amalgamate together, the result being a protuberance orgbulge 8 on each outer ,Surface of thel work which resemble rivet' heads. y As the present process `is usually practiced the protuberancey 8 is Sur- The method of spot welding consisting in `assembling the work between annular shaped electrodes each having a slight depression in its Contact face, passing an electric current from one electrode to the other Fig. 3 is a cross-section through the work and applying pressure whereby the electrodes which initially only contacted with the work annulai'ly, ultimately'contact with the work over their whole faces and leavea -resultant bulge on the surface of the work v cavity in its Contact face, to opposite sides of the lapped plates to be welded, whereby the electrodes contact initially with the work lonly around said cavities, passing an electric Current from one electrode to the other andapplying pressure until the bottom of the whole mass of thework inline with the electrodes is welded together, the result -being a bulge on the Surface of the work res emblixig' a rivet head.

`3. The' method ofspot welding consisting in assembling the work between elecrounding a shallow'. depression in its conthe cavities in the electrodes contact with the work and continuing the pressure until trode's eaclrhavingv an vannular ridge surone electrode tothe other across the Work,

applying pressure by means of the electrodes and continuing the pressure until the depression in the electrodes contacts with and Iapplies pressure to the heated sectionof the work whereby bulges resembling rivet heads are formed on opposite sides of the work.

4f. The method of spot welding consisting in assembling the Work between electrodes each having an annular ridge surrounding a shallow depression in its contact face, passing an electric current from one electrode to the other` across the work and applying pressure by ineens of the electrodes until the work lls the depressions in the electrodes 15 whereby the whole area of the work bounded by the electrodes is united in a single weld c aractenized by a protuberance in the center.

Signed at ANew York, in the county of 20 New York and State of New York, this 6th day of May, A. D. 1920.

J ACOB. C. SANDER. 

